Ductless cooling system for a vehicle power storage unit

ABSTRACT

A battery of a vehicle is cooled by air from a cabin of the vehicle. The air from the cabin flows underneath a rear seat of the vehicle and to the battery.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to ductless cooling systems for vehicle powerstorage units.

2. Discussion

A battery for a Hybrid Electric Vehicle (HEV) may require cooling duringusage. Some HEVs use chilled air from a dedicated air conditioning unit.Other HEVs use fresh air from outside the vehicle. Still other HEVs useair from the cabin via a duct located on a side of the rear seat or in apackage tray.

SUMMARY

Embodiments of the invention may take the form of a system fordelivering air from a vehicle cabin to a vehicle power storage unit. Thesystem includes a floor pan, a vehicle seat, and a power storage unit toprovide power to move the vehicle. The vehicle seat and floor pan definean air passageway, underneath the vehicle seat, from the vehicle cabinto the power storage unit.

While exemplary embodiments in accordance with the invention areillustrated and disclosed, such disclosure should not be construed tolimit the claims. It is anticipated that various modifications andalternative designs may be made without departing from the scope of theinvention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front perspective view, partially exploded, of portions of acooling system for a traction battery module of a vehicle in accordancewith an embodiment of the invention and shows the pathway for air,indicated by dotted line arrow, from the vehicle cabin to the tractionbattery module.

FIG. 2 is a block diagram of the cooling system of FIG. 1 and shows thepathway for air, indicated by arrow, from the vehicle cabin to thetrunk.

FIG. 3 is a front perspective view, in cross-section, of portions of thecooling system of FIG. 1 taken along section line 3-3 of FIG. 1 andshows the pathway for air, indicated by arrow, from the vehicle cabin,through the enclosure, inlet plenum, and traction battery module, to thetrunk.

FIG. 4 is a rear perspective view of portions of the cooling system ofFIG. 1 and shows air, indicated by arrow, exiting the inlet plenum.

FIG. 5 is a front perspective view of the seal of FIG. 4 associated withthe inlet plenum.

FIG. 6 is a top perspective view of the support of the rear seat of FIG.1.

FIG. 7 is a bottom perspective view of the support of FIG. 6 and showsportions of the enclosure, as indicated by speckling, defined by thesupport.

FIG. 8A is a side elevation view of the rear seat, seal, and inletplenum of FIG. 1 and shows the seat in the upright position and sealedwith the seal.

FIG. 8B is another side elevation view of the rear seat, seal, and inletplenum of FIG. 8A and shows the rear seat in the folded position and notsealed with the seal.

FIG. 8C is a side elevation view of an alternative embodiment of therear seat, seal, and inlet plenum and shows the rear seat in the foldedposition and sealed with the seal.

FIG. 8D is a side elevation view of another alternative embodiment ofthe rear seat and inlet plenum and shows the rear seat in the foldedposition and attached with the inlet plenum.

DETAILED DESCRIPTION

A dedicated air conditioning unit to cool a traction battery may beexpensive and reduce cargo volume. Introducing fresh air from outside avehicle to cool a traction battery may present water and dust managementissues. Using cabin air to cool a traction battery delivered via ductslocated on the side of rear seats may present space, ingress/egress,complexity, and occupant comfort issues. Similarly, ducts passingthrough a package tray may pass directly under a rear window glass andmay be subject to preheating from a solar load. Additionally, ductsrequire clearances and reduce volume due to duct thickness.

Some embodiments of the invention provide a ductless cooling system thatdraws air from the vehicle cabin to cool the battery. A physical inletduct is not required. Instead, the rear seat and the floor pan form achamber for the inlet air stream. The air is drawn underneath the rearseat, through an inlet plenum connecting the seat to the battery, tocool the cells. The warm air, after the heat exchange, is then drawn bya fan and discharged from the battery system to an open volume such asthe vehicle trunk, vehicle outside, or other desirable space.

The inlet plenum may impede recirculation of air from the trunk to theinlet of the air stream. Sealing features, such as an oversized foamseal disposed along the interface between the inlet plenum and the seatback, may allow simple seat assembly and be designed to work, and seal,with a foldable seat back. As such, portions of the foldable seat may becontoured, at the interface with the inlet plenum, to promote suchsealing. For example, a parabolic or circular interface seat surface maybe used such that each radius in the seat curvature separates quicklyfrom the inlet plenum to minimize the shear between the foam and seatback as the seat is rotated.

Seat cushions may taper at the interface with the seat back. The tapersmay provide a seal to reduce air leakage from the sides of the seat andalso force the air to come from the front of the seat.

The ductless cooling system may support the seat cushion withoutaffecting the seat comfort or H-point. The system may provide an airspace underneath the seat, an air inlet to allow air to enter the airspace from the cabin, proper support that ensures customer comfort whenseated, and a dust/moisture filter or screen mesh to reduce the amountof dust/moisture entering the air space.

The support for the cushion may be provided via a seat cushion wirestructure, a bridge form, plastic or metal, to transfer the cushionloads to the floor pan, or support ribs that pass through an air cavityand serve as flow guiding vanes.

FIG. 1 is a front perspective view, partially exploded, of portions ofcooling system 10 for traction battery module 12 of vehicle 14 showingthe path of air, indicated by dotted line arrow, from the vehicle cabinto traction battery module 12. Portions of floor pan 16 and rear seat 18form enclosure 20 under rear seat 18. Enclosure 20 provides an airpassageway for air to travel, as indicated by dotted line arrow, fromthe vehicle cabin to traction battery module 12. As explained below, airtravels under seat 18 and into traction battery module 12.

FIG. 2 is a block diagram of cooling system 10 of FIG. 1 showing thepathway for air, indicated by arrow, from the vehicle cabin to trunk 26.Air travels first through inlet grille 22, which obscures occupant viewof dust filter 28 and enclosure 20, and into enclosure 20 under seat 18.Inlet plenum 24 directs the air from enclosure 20 to traction batterymodule 12 where it cools the traction battery. Outlet plenum 30 directsthe air from traction battery module 12 to fan 32. Fan 32 blows the airinto trunk 26.

In some embodiments fan 32 may be used to pull air from the vehiclecabin to traction battery module 12 through enclosure 20. Fan 32 may belocated before or after traction battery module 12. Fan 32 may also belocated in traction battery module 12. In other embodiments fan 32 maybe absent. In still other embodiments, other portions of system 10,e.g., dust filter 28, plenums 24, 30, etc., may be absent.

FIG. 3 is a front perspective view, in cross-section, of portions ofcooling system 10 of FIG. 1 taken along section line 3-3 of FIG. 1showing the pathway for air, indicated by arrow, from the vehicle cabin,through enclosure 20, inlet plenum 24, and traction battery module 12,to trunk 26. As discussed above, air may be pulled or pushed from thevehicle cabin by fan 32 (FIG. 2), if present and depending on itslocation, or air may be forced into cooling system 10 by a vehicleclimate control system (not shown).

FIG. 4 is a rear perspective view of portions of cooling system 10showing air, indicated by arrow, exiting inlet plenum 24. Inlet plenum24 includes seal 35. Seal 35 may be a soft, flexible material, e.g.,foam, capable of producing a substantially airtight seal between inlet24 and its interfacing parts. In the embodiment of FIG. 4, seat 18 is inthe upright position and inlet plenum 24 seals against rear seat 18.Inlet plenum 24 also seals against floor pan 16 via seal 35. As such, asubstantially air tight seal exists between enclosure 20 and inletplenum 24. Inlet plenum is mechanically connected, e.g., bolted, withtraction battery module 12 such that a generally air tight seal existsbetween inlet plenum 24 and traction battery module 12. In otherembodiments, inlet plenum 24 may be attached with traction batterymodule 12 in any desired fashion, e.g., adhered, bonded. A foam seal mayalso be placed between inlet plenum 24 and traction battery module 12.

FIG. 5 is a front perspective view of seal 35 of FIG. 4 associated withinlet plenum 24. In other embodiments, seal 35 may have a differentshape or design depending on the shape or design of inlet plenum 24, ifpresent, and its interfacing parts.

FIG. 6 is a top perspective view of support 34 of rear seat 18 ofFIG. 1. Support 34 forms the understructure for rear seat 18 on whichcushion material (not shown) may be placed. Support 34 includes opening36 which provides the inlet for air from the vehicle cabin intoenclosure 20. Inlet grille 22 and dust filter 28 (FIG. 2) cover opening36 to prevent unobstructed flow of air from the vehicle cabin toenclosure 20. Support 34 may be made, formed, or molded in anyconventional fashion.

FIG. 7 is a bottom perspective view of support 34 of FIG. 6 showingportions of enclosure 20, as indicated by speckling, defined by support34. The sides of enclosure 20 are defined by air passage walls 38, 40.The top of enclosure 20 is defined by upper air passage surface 42. Inthe embodiment of FIG. 7, air passage walls 38, 40, upper air passagesurface 42, and floor pan 16 cooperate to define enclosure 20 under rearseat 18. Divider 44 transfers occupant loads from rear seat 18 to floorpan 16 as well as promotes the desired air flow through enclosure 20.Support structures 46 within enclosure 20, likewise, transfer occupantloads from rear seat 18 to floor pan 16 as well as promote the desiredair flow through enclosure 20. Support structures 46 outside ofenclosure 20 transfer occupant loads from rear seat 18 to floor pan 16.Support structures 46, in the embodiment of FIG. 7, have a conicalshape. In other embodiments, support structures 46 may have any desiredshape, e.g., rib, pillar, etc.

FIG. 8A is a side elevation view of rear seat 18 having a parabolicshape, seal 35, and inlet plenum 24 showing seat 18 in the uprightposition. As described above, if seat 18 is in the upright position,seal 35 of inlet plenum 24 seals against rear seat 18.

FIG. 8B is another side elevation view of rear seat 18, seal 35, andinlet plenum 24 of FIG. 8A showing rear seat 18 in the folded position.In the folded position, rear seat 18 does not seal against seal 35 ofinlet plenum 24. As such, air from the vehicle cabin may flow directlyinto inlet plenum 24 and thus traction battery module 12.

FIG. 8C is side elevation view of an alternative embodiment of rear seat118, seal 135, and inlet plenum 124 showing rear seat 118 in the foldedposition. Portions of rear seat 118 have a circular shape with thecenter of rotation for the seat back being the center of the circularshape such that if rear seat 118 is in the folded position, seal 135 ofinlet plenum 124 seals against rear seat 118.

FIG. 8D is a side elevation view of another alternative embodiment ofrear seat 218 and inlet plenum 224 showing rear seat 218 in the foldedposition and attached, e.g., bolted, with inlet plenum 224. Inlet plenum224 has an accordion-like configuration that permits it to extend andretract as rear seat 218 moves between the upright and stowed positionswhile maintaining its seal with rear seat 218.

Embodiments of the invention enable cabin air to be delivered to abattery system, reduce cost and weight required to route air to abattery system, and reduce the number of parts and labor associated withassembly processes. Embodiments of the invention also occupy less volumeresulting in increased room for airflow and seat cushions and are robustto floor pan dimensional variation caused by, for example, the presenceof dampening materials.

While embodiments of the invention have been illustrated and described,it is not intended that these embodiments illustrate and describe allpossible forms of the invention. Rather, the words used in thespecification are words of description rather than limitation, and it isunderstood that various changes may be made without departing from thespirit and scope of the invention.

1. A system for delivering air, in a vehicle, from a vehicle cabin to avehicle power storage unit comprising: a floor pan defining a bottom ofthe vehicle cabin; a vehicle seat; and a power storage unit, locatedbehind the vehicle seat, to provide power to move the vehicle, thevehicle seat and floor pan defining an air passageway, underneath thevehicle seat, from the vehicle cabin to the power storage unit.
 2. Thesystem of claim 1 further comprising an inlet plenum, disposed betweenthe air passageway and the power storage unit, to direct air from theair passageway to the power storage unit.
 3. The system of claim 2wherein the vehicle seat further includes a seat back moveable betweenupright and stowed positions and wherein the inlet plenum has a bellowsconfiguration and is attached with the seat back to form a substantiallyair tight seal between the inlet plenum and seat back.
 4. The system ofclaim 2 wherein the inlet plenum includes a sealing surface and whereina portion of the sealing surface seals with the floor pan to form asubstantially air tight seal between the inlet plenum and floor pan. 5.The system of claim 2 wherein the inlet plenum includes a sealingsurface and wherein a portion of the sealing surface seals with thevehicle seat to form a substantially air tight seal between the inletplenum and vehicle seat.
 6. The system of claim 5 wherein the vehicleseat further includes a seat back moveable between upright and stowedpositions and wherein the portion of the sealing surface seals with thevehicle seat if the seat back is in the stowed position.
 7. The systemof claim 5 wherein the vehicle seat further includes a seat backmoveable between upright and stowed positions and wherein the portion ofthe sealing surface does not seal with the vehicle seat if the seat backis in the stowed position.
 8. The system of claim 1 further comprisingan outlet plenum, associated with the power storage unit, to direct airfrom the power storage unit to a trunk of the vehicle.
 9. The system ofclaim 1 further comprising a fan to draw air from the vehicle cabin intothe power storage unit via the air passageway.
 10. The system of claim 1wherein the vehicle seat further includes a load bearing member totransfer occupant loads from the vehicle seat to the vehicle and whereinthe load bearing member defines a portion of the air passageway.
 11. Thesystem of claim 1 further comprising an air filter to filter air fromthe vehicle cabin.
 12. A system for delivering air, in a vehicle, from avehicle cabin to a vehicle power storage unit comprising: a floor pandefining a bottom of the vehicle cabin; a vehicle seat including a loadbearing member to transfer occupant loads from the vehicle seat to thevehicle; a power storage unit, located behind the vehicle seat, toprovide power to move the vehicle, the load bearing member and floor pandefining an air passageway, underneath the vehicle seat, from thevehicle cabin to the power storage unit; and an inlet plenum, disposedbetween the air passageway and power storage unit, to direct air fromthe air passageway to the power storage unit.
 13. The system of claim 12wherein the inlet plenum includes a sealing surface and wherein aportion of the sealing surface seals with the floor pan.
 14. The systemof claim 12 wherein the inlet plenum includes a sealing surface andwherein a portion of the sealing surface seals with the vehicle seat.15. The system of claim 14 wherein the vehicle seat further includes aseat back moveable between upright and stowed positions and wherein theportion of the sealing surface seals with the vehicle seat if the seatback is in the stowed position.
 16. The system of claim 14 wherein thevehicle seat further includes a seat back moveable between upright andstowed positions and wherein the portion of the sealing surface does notseal with the vehicle seat if the seat back is in the stowed position.17. The system of claim 12 further comprising an outlet plenum,associated with the power storage unit, to direct air from the powerstorage unit to a trunk of the vehicle.
 18. The system of claim 12further comprising a fan to draw air from the vehicle cabin into thepower storage unit via the air passageway.
 19. The system of claim 12further comprising an air filter, associated with the vehicle seat, tofilter air from the cabin.
 20. The system of claim 12 further comprisingan inlet grille, associated with the vehicle seat, to obscure the airpassageway from occupant view from within the vehicle cabin.